Post

Phosphorous ineffective for sunflowers

New research on the use of fertilizers in sunflower production indicates a popular nutrient is largely ineffective.

North Dakota State University Extension soil specialist Dave Franzen recently completed a study in hopes of updating decades-old fertility recommendations for growing sunflowers.

He says one finding that some producers might consider a “bombshell” was when using phosphorous, it rarely led to a yield increase.

“Out of more than 30 sites, we only had three that were statistically different than (fields) with no phosphorous treatment.  And only one of those three (that were different)  would’ve given the farmer a small economic benefit.”

He tells Brownfield a separate study of 40 sites in Nebraska showed sunflowers had no response to phosphorous.

Franzen says roughly 90 percent of sunflower growers are using phosphorous in their fertilizer program because the old recommendations say they should.

“If it’s written down and farmers have been doing it for 30 years, they just (keep on) doing it.”

Franzen says his and other modern studies prove applying phosphorous won’t help or hurt the plant, and there’s no economic benefit to incorporating the nutrient into a sunflower fertility program.